The invention is based on a method as defined hereinafter.
Such a method is known from European Patent Application 0 189 082. This method is used to make for a uniform brake action at the friction-affected brakes of a vehicle that is also equipped with a wear-free retarder, and to protect the brakes from overload. To this end, temperature signals from the wheel brakes that characterize the brake action are detected and evaluated in a control unit. If there is an overload on the friction-affected brakes, which is exhibited by excessive temperatures of the brake linings, the control unit reduces the brake value transducer signal at the applicable brake or brakes. However, a vehicle is endangered not only by a brake overload, but also if a brake's action is inadequate. This can happen if overly slightly brake outputs cause the brake linings not to reach the temperature above which so-called glazing is prevented.
This change in the brake lining surface, which lowers the coefficient of friction .mu., occurs to an increased extent in asbestos-free brake linings, which are increasingly used in vehicle brakes. If a vehicle is equipped with a wear-free auxiliary brake, then for reasons of economy the result will be a reduced load on the friction-affected service brake, which runs the risk of glazing of the brake linings. In a vehicle with glazed brake linings, only reduced braking action is available in an emergency braking situation.